1. Field
This invention generally relates to the treatment of morbid obesity and, more specifically, to a system and method for treating morbid obesity using a variably cycled percutaneous balloon implanted in the gastric cavity.
2. General Background
Morbid obesity is a major health problem confronting the general public and health care industry today. It is estimated that approximately 50% of the U.S. population is overweight and over ten million Americans are more than 100 pounds over their ideal weight. Generally, a person is considered morbidly (or seriously) obese if they are 100 pounds or more over their ideal weight. The morbidly obese group faces increased health risks including a higher likelihood of heart disease, hypertension, diabetes and certain cancers. Over 300,000 Americans die of obesity related illnesses each year. In addition, the morbidly obese generally have lower self-esteem and are more likely to suffer from depression than the general public.
Most obese individuals have struggled unsuccessfully with their weight for a lifetime. The numerous diets, behavioral therapy and treatments such as hypnosis, pituitary hormones and appetite suppressant drugs attest to the great difficulty many overweight people have in losing weight and keeping it off. Some of these weight loss strategies can be successful in the mildly obese people, but nearly all fail in individuals considered morbidly obese. These disappointing results have led many patients and their doctors to consider surgery as an option for weight loss.
Surgical techniques bring about weight loss primarily by limiting how much the stomach can hold. Today's most common surgical procedures to promote weight loss focus on decreasing food intake by restriction. Gastric banding, gastric bypass and vertical-banded gastroplasty are surgeries that limit the amount of food the stomach can hold by closing off or removing parts of the stomach. Other surgeries attempt to permanently fill the stomach with an inflated balloon. These treatments are invasive, require major surgery with hospitalization and are associated with complications.
The success rates of current treatments and procedures have been poor. With the restrictive procedure, the patient is usually limited to eating very small amounts of food at a time. For many people, this can create a “satisfied” feeling, but they often do not feel “full”. The ability to eat a large amount of food at one time is lost; consequently, many patients return to eating excessive amounts of high calorie or high sugar liquid foods. Essentially, their diet includes milk shakes and ice cream.
As to the balloon procedure of the past, very limited positive results were achieved. The balloon was relatively small when compared to the overall volume of the morbidly obese stomach. This is due to physiological limitation on the balloon volume. That is, complications of the device precluded enlarging it to a volume that would occupy more of the stomach. Yet, in order for the balloon to achieve a patient's feeling of fullness and satiation, the balloon would need to occupy a large portion (volume) of the patient's stomach. A balloon occupying this much volume without fixation or an inflation/deflation cycling has the potential of blocking food flow and causing necrosis of the stomach wall, ulcers and/or bleeding.
Moreover, success depends on the ability of a treatment to “normalize” not only the mechanical and neurohormonal sensation of feeling full and satiated, but also involves psychological factors. Both the mechanical and neurohormonal factors relate to one's need to feel “full” and “satiated”. Chemicals released by the stomach during the digestive process largely drive these factors. In other words, filling the stomach or limiting its pouch size controls these chemicals. Current surgical approaches, however, fail to achieve this global feeling of “satiety” response as they restrict food entry only into the small proximal stomach pouch and bypass the distal stomach where most of the neurohormonal chemical are normally released. Medical therapy is focused almost exclusively at the brain level and is likely to continue to fail as patients experience mood disorders and complications from medications. Accordingly, there is a need for a system and method for treating morbid obesity by restoring or normalizing the appropriate “fullness signals” from the stomach itself as this is the organ that regulates fullness. In particular, the system and method of the invention should cause a feeling of satiety from the stomach itself with less consumption of food by a morbidly obese patient.